Question

Can a body be in equilibrium if it is in motion?

Answer 1

The condition of equilibrium arises when the vector sum of all the forces acting on the system comes out to be zero. The state of the rest of the body is known as stability and equilibrium is known as the state of balance of the body. When the body is in equilibrium then the position of the body does not change unless an external force is applied to it.

Complete step-by-step solution:
Equilibrium is a type of situation in which the state of motion of the system and the internal energy of the system does not change with time. The net force that acts on the body comes out to be zero in equilibrium and all the opposite forces cancel out each other.
In physics, equilibrium is of two types, one is static equilibrium and another one is a dynamic equilibrium. The condition of dynamic equilibrium occurs when the body is in the state of equilibrium but it is still moving and the condition of static equilibrium arises when the body is in its state of equilibrium but it is still at rest.
In static equilibrium, all the forces that are acting on the systems are balanced and the system does not move. The concept of static equilibrium is used in designing rigid structures. The rigid structure consists of a bridge or floor of the house and these rigid structures must maintain static equilibrium in all the loading conditions.
Equilibrium can also be classified further. It can also be classified into three types- stable equilibrium, unstable equilibrium, and neutral equilibrium.
So according to the second law of motion, we know that the bodies that are in equilibrium will have constant acceleration because the forces acting on the body are zero and hence the object moves with constant velocity but it remains in its state of equilibrium and such type of equilibrium is known as dynamic equilibrium. so we can say that a body having equilibrium can also be in motion with constant velocity.

Note: When none of the forces acts on the body to move it in a line then it is known as translational equilibrium and when no forces act on the body to make it rotate then the body is said to be in rotational equilibrium. Homeostasis is the condition in which the body needs to maintain a state of equilibrium.